地铁高架桥上部结构及整体道床振动特性研究

Vibration Characteristics of the Superstructure and the Monolithic Track Bed of Metro Viaduct

以宁波轨道交通1号线高架桥为例,通过现场试验,从振动加速度级、振动加速度频谱及振动加速度级1/3倍频程等三个方面,对钢轨、道床、顶板、翼缘板、腹板及底板的振动进行对比分析,得到了各部分振动的振动加速度级、卓越频率及振动在整体道床与高架桥梁上部结构的传递规律.结果表明,钢轨的振动加速度级最大,道床、顶板、翼缘板、腹板及底板的振动加速度级相近;道床、顶板、翼缘板、腹板及底板的振动加速度都在低频段40~70 Hz范围内取得卓越频率;道床、顶板、翼缘板、腹板及底板的振动加速度级1/3倍频程曲线都比较相近,振动频谱特性没有发生明显变化.

Taking the viaduct of Ningbo Rail Transit Line 1 as an example, through field test, from the three aspects of the vibration acceleration level,the vibration acceleration spectrum and the vibration acceleration level 1/3 octave, we make comparative analysis of vibration of rail, ballast, roof,flange plate,the web plate and the bottom plate. The vibration acceleration level,the frequency of the vibration and the transmission law of the vibration in the track bed and the upper structure of the elevated bridge are obtained. The results show that the rail vibration acceleration level is the highest,and the vibration acceleration level of ballast, roof, flange,the web plate and the bottom plate are similar. The vibration acceleration of ballast, roof, flange,the web plate and the bottom plate have excellent frequency in the range of 40-70 Hz. Vibration acceleration level 1/3 octave curve of ballast, roof, flange,the web plate and the bottom plate are close and vibration spectrum characteristics don’t change significantly.